| AVS 60th International Symposium and Exhibition | |
| Graphene and Other 2D Materials Focus Topic | Wednesday Sessions |
| Session GR-WeM |
| Session: | 2D Materials on Metallic Substrates |
| Presenter: | P. Mende, Carnegie Mellon University |
| Authors: | P. Mende, Carnegie Mellon University Q. Gao, Carnegie Mellon University M. Widom, Carnegie Mellon University R.M. Feenstra, Carnegie Mellon University A. Ismach, University of Texas at Austin H. Chou, University of Texas at Austin R.S. Ruoff, University of Texas at Austin |
| Correspondent: | Click to Email |
Because of its structural similarity with graphene (~2% lattice mismatch), its atomically smooth surface, and lack of charge traps, hexagonal boron nitride (hBN) serves as an ideal candidate both as a substrate for graphene based devices, as well as an insulating layer in graphene-based heterostructures. Following the success achieved in the growth of graphene by chemical vapor deposition (CVD) on metal substrates, many investigators have pursued similar avenues in the synthesis of hBN. In this work, results are presented of low-energy electron microscopy and µLEED studies of hBN grown on polycrystalline Ni substrates by CVD. Low-energy electron reflectivity (LEER) spectra are acquired from surface regions containing various thicknesses (1 – 6 monolyers) of hBN on Ni. Distinct differences in the spectra are found in the low energy (0 – 10 eV) range, with a series of reflectivity minima observed, and the number of such minima being correlated with the thickness of the hBN. These results are consistent with prior work on multilayer graphene, in which it was demonstrated that interlayer states localized between the graphene layers give rise to the reflectivity minima found in the LEER spectra [1]. Theoretical simulation of the spectra using a first-principles method [1] is used to provide a basis for interpreting the experimental results. With the LEER spectra, it is found that the number of layers in multilayer hBN can be confidently determined, and maps of the hBN thickness over the surface are thus obtained.
This work was supported by STARnet, a Semiconductor Research Corporation program sponsored by MARCO and DARPA.
[1] R. M. Feenstra, et al., Phys. Rev. B 87, 041406(R) (2012).